Lock



Jan. 13, 1925.

K HOEPFNER LOCK Filed Dec. 15, 1923 lNVEA/TOR. 3 M WW W/TNESSES.

Patented Jan. 13, 1925.

KARL HOEPFNER, 015 DETROIT, IMICHIGAN.

LOOK.

Application filed December 15, 1923. Serial No. 680,968.

T all whom it may concern:

Be it known that I, KARL Honrrnnn, residing at Detroit, in the county of Wayne and State of Michigan, have invented certain new and useful Improvements in Locks, of which the following is a specification.

This invention pertains to looks in which the lock bolt is eliminated and the latch bolt serves as lock bolt when so desired.

The object of my invention is to produce a lock simple and inexpensive in construction, combined with the greatest safety.

Another object is the radical departure from the heretofore well known complicated, 5 irregular shape of the tumbler, which in my invention consists of a round pin.

lVith these objects in view, my invention is illustrated in the accompanying drawings, forming a part of this specification, in

which:

Fig. 1 is an inner side view of the lock withthe knob spindle shown in section on line wa of Fig. 3;

Fig. 2 is a front view of the lock when fastened to the door, both knobs are broken away;

Fig. 3 is a section. of the line bb of Fig. 1, showing the arrangement of the tumbler and the keyhole;

Fig. 4; is a side view of the lock, visible from the outside of the door;

Fig. 5 is a front view of the keyhole disk;

Fig. 6 shows the key.

In the drawings, 1 represents the casing with suitable drilled holes in which the cylindrical latch bolt 2 is guided. A diametrically reduced portion of the latch bolt carries a helical spring 3, which being confined between the thus formed shoulder of the latch bolt and the casing presses the latch bolt constantly outward. Rack teeth out in the latch bolt, engage corresponding teeth of the knob spindle 4:. This knob spindle is of tubular shape, and is rotatably mounted in the casing and an outer shield 5, the former being inserted on the inside of the door, the latter being placed against the outside of the door and both drawn together and secured to the door by two screws 6.

5o Protruding from the knob spindle and forming a communicating chamber with the bore thereof, is a cylindrical extension in which is guided a round pin 7. A helical spring 8, carried by said pin and pressing against a shoulder thereof, forces this pin constantly inward against a rotary cam 9, placed in the bore of the knob spindle. The cam is formed on a cylindrical body extending from the knob spindle on the inside of the door, and for the purpose of enabling any person to turn the cam, is provided with a knob portion 9 To prevent lengthwise movement of the cam, and to limit the rotation thereof, a slot 9 is provided; to turn the cam from the outside of the door a slot 9 is cut on the end thereof, in which is inserted the key, as will be described later.

When the pin 7. is resting against the flat surface representing the diameter of the rotary cam, its other end will just clear the casing; turning the cam 180 will force the pin outward and cause it to enter a recess in the casing; thus the knob spindle and consequently the spring pressed latch bolt are held in looking position. It will be observed that two recesses, diametrically opposite, are formed in the casing, which is for the purpose of using the casing on right or left hand looks as the occasion may demand.

Inorder that the pin 7 when arresting the latch bolt may positively enter the recess of the casing, the knob spindle is provided with a lug l which striking a boss 15 on the inside of the casing, terminates the movement of the latch bolt and consequently places pin and recess in alignment.

A knob 10, secured to the knob spindle on the inside of the door, and a knob 11, secured to the outside thereof, are for the obvious purpose of actuating the latch bolt. The means for securing the knobs 10 and 11 to the spindle, are the set screws 12 and 13, respectively; the former entering thru a hole of the spindle into the slot 9 of the cam, for the purpose previously described. In the drawing Fig. 2, it will be observed that it is impossible to insert a screw driver into the slot of set screw 13 when the lock is fastened to the door as shown; this being accomplished by the semi-circular projection on the outer shield covering the set screw. In order to remove the screw 13 it is necessary to first withdraw the screws 6, then the shield is given half a turn on the knob spindle and the screw removed. The set screw 13, extending into the bore of the knob spindle, and likewise the segmentally shaped pieces 14, which are inserted diametrically opposite in the knob spindle, allow only a flat key conforming in thickness to the slot 9 to enter the knob spindle. It is obvious that several segmental pieces at any desired distance from each other may be inserted, thereby giving a great variety of keys.

The hole of the knob 11 is of two difierentdiameters, thereby forming an abutment for a disk 16 placed inside the knob, a similar disk 17 also in said knob rests against the end of the knob spindle. Both disks are slidingly connected to each other by two pins 18 fastened in disk 16 and extending intocorresponding holes in disk 17 while a helical'spring 19 placed between said two disks forces them apart. A rivet 20, driven into the knob 11 and extending into the larger bore, prevents rotation of the disks, when its head enters either one of the two recesses formed in the periphery of disk 16, and unless this disk is pushed inward to clear the rivet it cannot beturned by the key 21 inserted into the keyhole of said disks. For this purpose, a projection 22 is formed on the key, which is also provided I with several slots to clear the set screw 13 and pieces ltithus'providing two separate means of safety.

It will be readily understood that the particular shape and arrangement of the several parts may vary from the construction here shown and that I may use a different formed key and omit one or several parts without departing from the spirit of myinvention.

Having thus described my invention, I claim: 7 a Y 1. In a lock, the combination with the casing, a spring pressed cylindrical latch bolt with rack teeth formed thereon, a

tubular knob spindleprovidedwith teeth to engage said latch bolt, a chamber communicating with the bore of said knob spindle formed by a protusion thereon, a spring pressed pin in said chamber, a rotary formed on the outer shield to render impossible the removal of the knob holding means, substantially as described.

2. In a lock, the combination with the casing, a spring pressed cylindrical latch bolt with rack teeth formed thereon, a tubular knob spindle provided with teeth to engage said latch bolt, a chamber'communicating with the bore of said knob spindle formed by a protrusion thereon, a spring pressed pin in said chamber, a rotary cam in said knob spindle, rotation of said cam to cause said pin to enter arecess in cam in said knob spindle, a projection the casing thereby arresting the knob spindle V and the latch bolt, a projection on the outer shield to render impossible the removal of the means for holding the outer knob,-mans in the outer knob to prevent rotation ofthe KARL HOEPFNER. IVitnesses: V l i' H. V. RAYMOND, GRACE E Bn rnnn. 

